**the following is a transcript from the Calm Cash Podcast episode from season 1 episode 36 titled "Food & Your Feelings"
Hi and welcome to Calm Cash. I’m your host Ben Jackson. You’ve probably heard the phrase “you are what you eat”. And everywhere you look there is science or research that confirms that. Our food intake has been linked to cardiovascular disease and some cancers but there hasn’t been too much discussion until recently about how food affects our emotions and mental health. But the research and science in this space is emerging and showing us some incredibly compelling links between the food we eat and our feelings. So today, let’s go deeper into how what we eat impacts our mental health and how making the right decisions can lead to a happier you.
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It has officially been 6 months of working from home for me. That bizarre milestone happened this past week. During this time, I’ve gone back into the office exactly once. The day I did, I was one of two people on my entire floor that day. It has seating for 147 people. What that weird experience taught me was I don’t miss the office…I miss the people. And when I reflect on the time I spend with co-workers socially when at work, so much of it revolves around food.
Whether I’m going to get a coffee and chat with a teammate, grab a beer after work or we are celebrating a birthday, a promotion or holiday, there is food. And definitely there are cookies. So many cookies. And the problem is I love cookies, and pie and I hate brownies but I eat those too when everyone else is eating them. It doesn’t take long for me to give in to that peer pressure even though the world is full of bad brownies. If you make good brownies, please email me because, yes, I’m interested.
After 2 months of working from home, I lost 6 pounds and that was with a new born so it wasn’t like I was really exercising a ton. I just stopped eating so much of those amazing desserts and drinking those beers after work. And we were making our own meals a lot then. Well the problem now is at the 6 month mark of working remotely, I’ve gained all that weight back plus a pound or two. Not great! And on top of it, I’ve been feeling mentally and emotionally pretty crappy about it. The culprit this time appears to be not having lots of time to exercise or cook like we were doing meaning lots of take-out food and ice cream. There has been so much ice cream because my wife has a sweet tooth like me.
I think we all understand that our physical health and our mental health are connected. But I wanted to take that a layer deeper by asking the question: can what we eat impact our mood and mental health directly? Or maybe said differently, does what we eat affect how we feel? After lots of reading and research, the answer is most definitely. And this search for an answer brought me to a field of science I had never even heard of…nutritional psychiatry.
Nutritional psychiatry is an emerging field of science that is now supported by a number of studies that show the impacts of food on our mental health. If you are skeptical right now, I totally get it because I was too and then I started reading research and data from Harvard Medical School on the subject and it changed my perspective. This is real. And legit, hard-core scientists and researchers at the best institutions in the world are looking at this.
Ok nutritional psychiatry, you have my attention.
There is this great article from Dr. Eva Selhub from Harvard called “Your brain on food” and it totally blew me away. Of course we know that our brains are always on. It’s up 24/7 even though we aren’t. But it made me stop and think about why we actually eat. Have you ever actually thought about that? We eat to fuel our brain so we can move, talk, breathe and stay alive. It is that simple. And what we eat directly affects the structure and function of our brains and ultimately our mood. Now let’s get to the mind blowing part…at least for me.
Let’s talk about serotonin. And now you are probably confused because that is the stuff we take to make us fall asleep right? I was too. Just hang tight. So serotonin is a neurotransmitter that does in fact help regulate our sleep but it also helps regulate our appetites, and our moods and it even plays a major role in how we feel and perceive pain. Now the crazy part. About 95% of the serotonin your body makes is produced in your gastrointestinal tract. And your GI tract is lined with 100 million nerve cells called neurons that help you digest food sure but also these neurons activate a neural pathway that connects your gut directly to your brain. Scientists call it the gut-brain axis. Your digestive system isn’t just about processing food and getting nutrients, it is guiding your emotions. And when we eat healthy foods that influence the good bacteria in our microbiome, we generate more serotonin improving our mood and those good bacteria create barriers against toxins, inflammation and bad bacteria which are all serotonin killers.
So let’s talk about some of the studies and findings that scientists have discovered linking our food and our feelings. A 2017 study showed that depressive symptoms like mood and anxiety could be improved in patients who focused their diet on fresh and whole foods while limiting processed, refined foods, sweets and fried foods. In fact, 32% of the participants in the study improved so much that their depression was classified as in remission. After 12 weeks of counseling and eating right, they were no longer depressed. That is fascinating to me.
Another study found that a Western diet, which includes sugary drinks like Coke, refined grains, fried foods, processed meats, high fat dairy and sweets increased risk of depression between 25 and 35% compared to a Mediterranean diet and traditional Japanese diet. What the other diets have that fewer and fewer Western diets feature is fish and seafood, tons of fresh vegetables and fruit with modest amounts of lean meats and dairy.
And one final research study about probiotics specifically. Dutch research divided study participants into 2 groups. One group got a placebo and the other group received a probiotic supplement for 4 weeks. The people that got the probiotic reported experiencing less sadness, a reduction in aggressive thoughts and as the study says experienced less “rumination”. In the US we would probably say those people were less obsessive over negative thoughts or over-thinking. The conclusion of the Dutch researches was the type and amount of bacteria in your digestive tract impacts your mood and it all comes back to that gut-brain axis.
Additionally, people who are obese have been shown in studies to have higher risk for mental health issues like depression and other mood disorders. Researchers believe the increased risk is due to hormonal and immunological changes that occur in people who are overweight.
So let’s talk about some foods to avoid and then what we should be prioritizing in our eating to give our body the best fuel and improve this relationship between our belly and brain. First, as we’ve talked about before, limiting alcohol is a good idea when considering food and drink and our mental health. There are clear links between alcohol and depression, anxiety and other issues like substance dependence and abuse not to mention other complications like accidents, relationship issues with family and friends and the physical damage it can take on your body.
Second, refined foods or convenience foods like fast food and junk food are high in calories and low in the good stuff like nutrients and antioxidants. Processed foods that contain sugar and refined carbs may contribute to mood disorders like depression and anxiety. They can also lead to inflammation and are generally not good for those neurons in our GI tract.
Another source of inflammation and food that can impair brain function are processed oils like hydrogenated oils that are found in tons of processed foods. Safflower and corn oil are also fats to avoid because of their negative nutritional impact. Make sure to check the labels for these bad news ingredients.
Lastly, refined sugars like high fructose corn syrup, white and brown sugar, cane sugar and molasses have been studied to impair brain function. In addition to worsening how we regulate insulin, these sugars promote inflammation and oxidative stress on our bodies. And of course these sugars are everywhere, from the cookies at work that I loves so much even to things like bread, pasta, salad dressings, ketchup and peanut butter.
But not all sugars are terrible. If you need something sweet, opt for a natural sugar like fructose which is found in fruit like blueberries and strawberries. In addition to tasting delicious, you will get antioxidants that help protect your cells against free radicals that contribute to heart disease, cancer and have been linked to mental health issues.
You may be saying, of course eating fruits and vegetables is obvious and I already know that. And you also know to cut down on fast foods, processed foods and drinking a bunch of cokes. That information is pretty much everywhere these days so we won’t spend time there. Instead, here are some lesser known or discussed foods, vitamins or nutrients your body needs to be healthy both mentally and physically.
Let’s start with selenium. It is a powerful antioxidant that helps fight oxidative stress from things like those refined sugars but there is also science that says it helps improve mood and reduce anxiety. You can find selenium in brazil nuts and seafood like tuna, oysters, shrimp and it is also in shiitake mushrooms. If you don’t care for those foods, you can take a selenium supplement to boost your intake and hopefully your mood too.
Next let’s talk about vitamin D which may help improve the symptoms of depression according to a 2019 study. Most of us get our vitamin D through sun exposure but we can also get it from our food by eating things like eggs, cheese and oily fish like salmon and tuna. Apparently beef liver is high in vitamin D as well but there is a zero percent chance I’m eating that. Like selenium, you can take a supplement but I say try to skip it and get outside and catch some rays. One other really interesting note about vitamin D. There is research about COVID and vitamin D that shows higher levels of this vitamin may reduce the severity of symptoms. The research is still very early but anything that lessens the potential impact of COVID symptoms sounds worth it to me, especially when it is also good for us in other ways.
Zinc is the next item to discuss for our diets. Zinc helps your body perceive taste but it has also been linked to an improved immune system and influencing depression and anxiety. Studies show that people who suffer from some mental illnesses like depression have lower levels of zinc and that adding zinc in your diet or with supplementation can help with mental health. You can find zinc in whole grains, oysters, lean proteins like chicken and pork and in beans, nuts and seeds like pumpkin seeds.
Lastly lets’ go back into our microbiome and talk about probiotics. We saw in the Dutch study that they’ve been proven to help with mood but which foods are good for boosting the right kinds of good bacteria via probiotics? Start with fermented foods because they are the most natural source of probiotics according to another Harvard Medical School article. Fermenting is one of the oldest techniques for food preservation. Mankind has been fermenting foods and drinks like beer and wine for centuries. Foods that are fermented go through a process of lactofermentation where natural bacteria feed on the sugar and starch in the food, creating lactic acid. This process creates an environment that preserves the food and promotes beneficial enzymes, B vitamins, and omega-3 fatty acids, as well as various species of good bacteria.
The best foods for these healthy probiotics include yogurt, sauerkraut, miso, pickles, kimchi and one of my favorite drinks, kombucha. Some soft cheeses like gouda and gruyere have probiotics too. One of the downsides is these foods can have a pretty strong taste so if they are too funky for your palate, you can also take supplement in pill or powder form.
And one last thing before we wrap up. We aren’t robots and sometimes we all need a treat or a break. I’m not giving up cookies forever. In fact I will probably have one soon but I will be limiting how often and how many I’ll allow myself to eat. To sustain your healthy behaviors over the long run, you have to give yourself a cheat day or two. In fact the science is starting to back that up too.
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I hope you learned something new about the connection between what we eat and our moods, emotions and overall mental health. This space is fascinating and as the field of nutritional psychiatry evolves, you will definitely hear more about it on Calm Cash. Here’s to healthy eating that will lead you to more happiness. Stay safe and I’ll see you next week.